Washington

[kkt]

When I see the name Parkway, I think of a road that's landscaped on both sides, like a Road through a Park.  Not a few miles of strip mall.

[jakeroot]

Likewise, I don't think of a 40 mph arterial with three hundred traffic lights as a "speedway".

Something brand new would be way cooler. Maybe "Terminal Way".

[kkt]

You're gonna die if you go that way?

[jakeroot]

You're gonna die if you go that way?

[Mukilteo Ferry] Terminal Way.

There are quite a few other "Terminal Way" designations in other parts of the country, chiefly near airports or other cargo-handling places.

[pderocco]

Likewise, I don't think of a 40 mph arterial with three hundred traffic lights as a "speedway".

Depends on how they time the lights.

[TEG24601]

You're gonna die if you go that way?

[Mukilteo Ferry] Terminal Way.

There are quite a few other "Terminal Way" designations in other parts of the country, chiefly near airports or other cargo-handling places.

It would be hilarious if WSDOT gets involved and they have to call is "Whidbey Island Highway" or "Whidbey Island Blvd", given how much distain residents of old Mukilteo have towards the ferry and ferry traffic.

[Bruce]

A new interchange on I-405 has opened at NE 132nd Street in Kirkland. A half-diamond with two roundabouts to serve Totem Lake and EvergreenHealth.

[The Ghostbuster]

How common are roundabouts in the state of Washington?

[Bruce]

How common are roundabouts in the state of Washington?

We've got a few hundred now apparently. Many intersections have been converted, but they're still somewhat rare in interchanges.

Multilane, high-traffic ones are very rare. Lake Stevens opened one months ago that is still having frequent collisions.

[jakeroot]

I wouldn't say they're "very rare" but, yes, a plurality of roundabouts are single-lane, but that's true throughout the US.

Unfortunately, it's true that they are usually accident hot-spots. Some that come to mind:

• WA-20 @ WA-20 Spur (Sharpes Corner): lane reductions have taken place;
• WA-510 (Marvin Rd) @ Pacific Ave (Lacey): lane reductions have taken place;
• Steptoe @ Columbia Park Trail (Richland): lane reductions have taken place, and the westbound approach had a meter installed;
• WA-16 @ Burnham Dr (Gig Harbor): both roundabouts were rebuilt to replace the original British design, but the western roundabout has undergone several changes (i.e. lane reductions) even after rebuilding.
• I-90 @ Bendigo Blvd (North Bend): lane reductions have taken place so many times, I lost count.

It remains to be seen if 405 @ NE 132nd will prove to be a mess like other multi-lane roundabouts. I'm cautiously optimistic, but the data seems quite telling.

[stevashe]

At the very least I expect traffic will move better through the intersections.

When NE 132nd St was part of my commute a few years ago, there was always a big backup because the lights on both sides of I-405 were so poorly coordinated, making half of the green time wasted since they didn't line up. Would have been nice to have these roundabouts since they don't have that problem!

To provide one example of a larger roundabout that hasn't had to be revised: US2 @ the Costco Entrance north of Spokane has remained the same since it opened in 2018. Though this one was actually designed by my company to have the option of adding more lanes later, so maybe that's a better strategy than throwing all the lanes in from the start!